Semen Quality is Associated with Sperm Aneuploidy and DNA Fragmentation in the United Arab Emirates Population.

Background: Sperm chromosome aneuploidy and the extent of sperm DNA fragmentation (SDF) are contributing factors to male infertility. Their extent can be measured using platforms such as sperm chromatin dispersion (SCD) and sperm fluorescence in situ hybridization (sFISH). Additional studies, however, are needed to understand the clinical applicability of these in vitro tests based on statistically validated thresholds. Aim: The primary objective of this study was to report the incidence of SDF and chromosomal aneuploidy with respect to sperm quality in the United Arab Emirates (UAE) population. In addition, we wished to establish clinically useful SDF and aneuploidy cutoff values. Materials and Methods: A total of 302 subjects were enrolled in this study. The control group consisted of n = 100 (33.11%) reproductively-proven fertile men, and the case group consisted of n = 202 (66.89%) infertile men. The sperm quality of the cases was further subclassified as normospermia ("Normo," n = 88; 43.56%); teratozoospermia ("T," n = 40; 19.80%); oligoasthenoteratozoospermia ("OAT," n = 37; 18.32%); asthenoteratozoospermia ("AT," n = 19; 9.41%); or oligoteratozoospermia ("OT," n = 18; 8.91%). The assessments of SDF were done using SCD tests. Chromosomal aneuploidy (Chr 13, 18, 21, X, and Y) was investigated using sFISH. Furthermore, based on the fragmentation index, cases were divided into subfertile groups defined as low, medium, high, and severe. The Mann-Whitney test was used to set the upper threshold value for sFISH, and the odds ratio was used for SDF assessment. Results: Cases having sperm quality "AT," "OAT," and "OT" together with the moderate, high, and severe subfertile groups had the highest DNA fragmentation indices: 31.58%, 27.03%, and 22.22%, respectively. In the sFISH analyses, groups with sperm quality "OAT," "T," and "OT" exhibited high degrees of abnormalities: 86.49%, 52.50%, and 50%, respectively. The most common chromosomal abnormalities found were "sex chromosome hyperploidy (XY18)" and "diploid (Chr 13, 21)." The incidences of sperm quality with respect to SDF and sFISH are also reported in detail. Conclusions: This is the first study in the UAE which shows SDF and sFISH incidences together with sperm quality. This study also establishes SDF and sFISH cutoff values for the UAE population.

Low Gonadotropin Dosage Reduces Aneuploidy in Human Preimplantation Embryos: First Clinical Study in a UAE Population.

TYPE OF STUDY: Retrospective analysis of embryo aneuploidy in patients undergoing in vitro fertilization (IVF) cycles. AIM: To evaluate factors that might affect the incidence of embryo aneuploidy during IVF cycles. METHODS: Three hundred twelve IVF cases were included in the present study. Preimplantation genetic testing for aneuploidy (PGT-A) was performed for all the subjects involved. Subject stratification was done based on maternal age, gonadotropin drug dosage, and IVF outcomes data. Maternal age <35 years were placed in the "Young" age group and age ≥35 years were placed in the "Advanced Maternal Age" group. Similarly, IVF drug administered <200 International units (IU) was considered "low dosage," group and ≥200 IU were considered "high dosage" group. Patients were stratified into four groups-group 1: age <35 years and administered <200 IU; group 2: age <35 years and administered ≥200 IU; group 3: age ≥35 years and administered at <200 IU; and group 4: age ≥35 years and administered ≥200 IU. PGT-A results were attained using a next-generation sequencing-based protocol. Embryo transfer was guided by transabdominal ultrasound. Statistical significance was calculated with the use of chi-square test. RESULTS: One thousand fifty blastocyst trophectoderm biopsies from 312 IVF cases were retrieved. The IVF outcome of a total of 105 normal cases resulted in 65.71% pregnancies. Stratifying for maternal age and IVF drug stimulation with PGT-A analyses we found the euploid embryo percentages equal to 37.59% in Group 1; 16.18% in Group 2; 22.44% in Group 3; and 2.59% in Group 4. Similarly the aneuploid embryo (percentage)s were 62.40% for Group 1; 83.81% for Group 2; 77.55% for Group 3; and 87.40% for Group 4. CONCLUSION: This is the first clinical study reporting that gonadotropin dosage may act as a contributing factor in increasing aneuploidy incidences for the patients undergoing IVF cycles in the UAE population. This study shows that in all patient age groups, lower drug stimulation leads to an increasing trend in embryo euploidy.

Validation of Next-Generation Sequencer for 24-Chromosome Aneuploidy Screening in Human Embryos.

BACKGROUND: Next-Generation Sequencing (NGS) is the latest approach for preimplantation genetic diagnoses (PGD). AIM: The purpose of this study was to standardize and validate an NGS method for comprehensive chromosome screening and to investigate its applicability to PGD. METHODS: Embryo biopsy, whole-genome amplification, array comparative genomic hybridization (aCGH), and semiconductor sequencing were employed. RESULTS: A total of 204 whole-genome-amplified products were tested with an NGS-based protocol, from which 100 samples were used for standardization and to evaluate the quality of the results produced by this new technique. The remaining 104 samples tested by NGS were previously analyzed by using the aCGH protocol to determine the sensitivity and specificity of this new technique. In total, 4896 chromosomes were assessed, out of which 196 carried a copy number imbalance. NGS sensitivity and specificity for calling aneuploidy was 100%. CONCLUSION: This is the first study reporting preclinical validation and accuracy assessment of the Ion Torrent Personal Genome Machine (PGM) NGS-based comprehensive chromosome screening method using blastomeres and blastocysts. The NGS proved to be a robust methodology and is ready for clinical application in reproductive medicine, with the major advantage of low cost and enhanced precision when compared with other technologies used for comprehensive chromosome screening.

Mutation analysis of the CFTR gene in 225 children: identification of five novel severe and seven reported severe mutations.

BACKGROUND: Cystic fibrosis (CF) is the most common inherited disorder in Caucasian populations, with more than 1400 cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations. The type of mutations and their distributions varies widely between different countries and/or ethnic groups. METHODS: We characterized the mutations in the CFTR gene by single-strand conformation polymorphism followed by sequencing in CF patients. RESULTS: Twelve mutations were found in 79/225 (35.1%) patients. The most frequent mutations were F508 deletion (31.1%), p.R1162× (2.2%), p.M1T (0.8%), and S559N (0.8%). Five novel severe mutations (p.R80N11fs*11, p.R75G, p.Y577×, p.Y808Yfs*10, and p.I331×) and three reported mutations (p.C343×, p.Ile1000×, p.M469V) were detected. CONCLUSION: The protocol for identification of mutations in cases of CF in developing countries would have to include a different set of mutations than those reported from western countries.

Use of ethnicity-specific sequence tag site markers for Y chromosome microdeletion studies.

INTRODUCTION: Microdeletions in the azoospermia factor region on the long arm of Y chromosome are associated with spermatogenic failure. There are many markers for the diagnosis of Y chromosome microdeletion analysis, but in routine practice only a limited set of markers can be tested. OBJECTIVE: The objectives of this study were to determine the frequency of Y chromosome microdeletion in idiopathic cases of male infertility in India, to attempt genotype-phenotype correlation, and to evaluate whether markers to be tested for diagnosis of Y chromosome microdeletion should be ethnicity specific. METHODS: Microdeletions in the Y chromosome were analyzed in 200 infertile males. The six sequence tag site (STS) markers prescribed by the European Academy of Andrology (EAA) were used initially. Patients in whom no deletions were detected by use of these markers were tested by markers selected from other studies from India. RESULTS: The STS markers prescribed by EAA detected deletions in only 6 (3%) of 200 infertile males. However, markers selected from previous Indian studies showed deletions in an additional 15 (7.5%) of infertile males. Overall, Y chromosome microdeletions were observed in 21 (10.5%) of 200 patients. Of these, 13 were cases of azoospermia and 8 were cases of severe oligospermia. CONCLUSION: The markers prescribed by EAA alone are not suitable for the diagnosis of Y chromosome microdeletions in infertile males. The protocol for identification of Y chromosome microdeletions in cases of nonobstructive azoospermia/severe oligospermia would have to include a different set of STS markers.

Mutation studies in the CFTR gene in Asian Indian subjects with congenital bilateral absence of vas deferens: report of two novel mutations and four novel variants.

BACKGROUND: Congenital bilateral absence of vas deferens (CBAVD) is a form of male infertility in which mutations occur in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The molecular basis of CBAVD is not completely understood, especially in developing countries. METHODS: We characterized the mutations/variants in the CFTR gene by single strand conformation polymorphism followed by sequencing in 35 CBAVD patients. None of the patients had systemic manifestations of cystic fibrosis. Fifty normal subjects were studied as controls. RESULTS: Mutations/variants in the CFTR gene were found in all CBAVD patients. Five mutations and 10 variants were detected in 35 patients. The most frequent severe mutation was F508del (34.2%) and the most common variant was IVS8-5T (54.2%). Two novel severe mutations (p.E217Gfs*11 and p.A1285V) and four novel variants (pT438A, c.4095+30insCT, c.-737G>A, and c.2909-92A>G) were detected. CONCLUSION: The protocol for identification of mutations in cases of CBAVD in developing countries would have to include a different set of mutations than those reported from western countries.